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who has shortened a chrome lined barrel?
3/11/2012 1:38:49 AM
I have consulted with a gunsmith who said he wont shorten a chrome lined barrel because there is no way to recrown it where the cutter doesn’t put micro fractures in the chrome which will then chip and effect accuracy. I figured that this would be the case before I even talked to him about it. Since I'm sure that lots of folks have had chrome-lined barrels shortened, my question is who has noticed any negative effects on accuracy?
3/11/2012 12:30:59 PM
It's not necessary to use a cutter to crown a barrel, you can use abrasives.
"Back in the day" gunsmiths would use a round head brass screw and valve grinding compound to crown a barrel.
A more technical method is to use a brass ball in a lathe.
I haven't seen that many cut off chrome lined barrels, and on those few I never saw any cracking, chipping, or flaking off.
In any case, I doubt you'd actually notice any accuracy loss, even if there was some.
"Back in the day" gunsmiths would use a round head brass screw and valve grinding compound to crown a barrel.
A more technical method is to use a brass ball in a lathe.
I haven't seen that many cut off chrome lined barrels, and on those few I never saw any cracking, chipping, or flaking off.
In any case, I doubt you'd actually notice any accuracy loss, even if there was some.
3/11/2012 1:31:38 PM
I had my 20" COLT M16A2 barrel cut, re-crowned, and re-threaded.
It's not an issue. industrial hard chrome is nothing like the thick brittle nickle chrome plating on your Daddys F-150 bumper.
for some reason, this rifle shoots AMAZINGLY small groups.
It's not an issue. industrial hard chrome is nothing like the thick brittle nickle chrome plating on your Daddys F-150 bumper.
for some reason, this rifle shoots AMAZINGLY small groups.
3/11/2012 2:03:55 PM
Not a problem.
The muzzle is crowned just like normal after the cut/re-threading, then using a taper crown clean up tool with lapping compound like normal, the edge of the bore to clown it cleaned up to remove edge burs (the every so slight taper at the end of the bore).
I have never bought into using a cutter to clean up the edge of bore to crown, since a tapper cutter ends up leaving a bur as well (what you are trying to clean up in the first place).
The muzzle is crowned just like normal after the cut/re-threading, then using a taper crown clean up tool with lapping compound like normal, the edge of the bore to clown it cleaned up to remove edge burs (the every so slight taper at the end of the bore).
I have never bought into using a cutter to clean up the edge of bore to crown, since a tapper cutter ends up leaving a bur as well (what you are trying to clean up in the first place).
3/11/2012 2:28:49 PM
My SBR barrel started life as a 14.5 DD.
Now it's a 10.5.
No accuracy issues at all.
Now it's a 10.5.
No accuracy issues at all.
3/12/2012 5:40:28 PM
Originally Posted By m1garand__man:
I have consulted with a gunsmith who said he wont shorten a chrome lined barrel because there is no way to recrown it where the cutter doesn’t put micro fractures in the chrome which will then chip and effect accuracy. I figured that this would be the case before I even talked to him about it. Since I'm sure that lots of folks have had chrome-lined barrels shortened, my question is who has noticed any negative effects on accuracy?
I have consulted with a gunsmith who said he wont shorten a chrome lined barrel because there is no way to recrown it where the cutter doesn’t put micro fractures in the chrome which will then chip and effect accuracy. I figured that this would be the case before I even talked to him about it. Since I'm sure that lots of folks have had chrome-lined barrels shortened, my question is who has noticed any negative effects on accuracy?
What he told you is accurate. Cutting a chrome lined barrels can and will cause the chrome to flake and peel back from the cut. Will this effect accurcy? Maybe, sometimes it will other times it won't. Does it happen all the time? No, but enough that rifle builders and gunsmiths won't do it for the complaint and liability point of view. If you find someone that will then he is the minority.
3/12/2012 6:05:08 PM
3/14/2012 12:51:24 PM
What he said.
